People learn something everyday, and a lot of times it's that what they the day before was .
The sentence describes how new learning often corrects yesterday's mistakes, so the first blank needs a verb about gaining knowledge and the second a word meaning incorrect. "Learnt ... wrong" fits: what they learnt the day before turned out to be wrong.
So the correct pair is learnt ... wrong.
If the price of a commodity increases by 25%, by what percentage should the consumption be reduced to keep the expenditure the same?